JP2016086999A - Ablation catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ablation catheter enabling therapeutic time to be shorter easily.SOLUTION: An ablation catheter comprises: a shaft 112 including a first distal portion 120 and a second distal portion 140; a connection mechanism 118 connecting the first distal portion and the second distal portion; a first heat element 122 and a second heat element 124; a first bending mechanism bending the first distal portion; and a second bending mechanism bending the second distal portion. The first distal portion includes a first region 121A and a second region 121C. The second distal portion includes a third region 141A and a forth region 141C. The connection mechanism is configured such that when the first distal portion and the second distal portion are bent, the first region and the third region are separated from each other so that at least a part of the first region and at least a part of the third region come into contact with a wall tissue of a lumen, and also the second region and the forth region are separated from each other so that at least a part of the second region and at least a part of the forth region come into contact with the wall tissue of the lumen.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an ablation catheter for performing ablation treatment in a living body lumen.

  The ablation catheter is disposed in the lumen in the living body, and is disposed on the shaft section, and heat denaturation is performed by applying energy to a treatment target site (lumen wall tissue) related to the diseased part in the living body. And is used to recover symptoms such as dysfunction caused by the disease.

  For example, when there are a plurality of treatment target portions, it is necessary to position the thermal element every time treatment is performed, and thus there is a problem that the treatment time becomes longer and the burden on the patient increases. In particular, when performing renal sympathetic nerve ablation, the operation of positioning the thermal element is complicated because treatment is performed on a plurality of renal sympathetic nerves that run irregularly on the outer surface of the renal artery.

  For this reason, in the ablation catheter, a plurality of thermal elements are arranged at different positions in the axial direction of the distal end portion of the catheter, and a plurality of treatments are performed at the same time, thereby shortening the treatment time (for example, Patent Document 1). reference.).

Special table 2012-513873 gazette

  However, the catheter as in Patent Document 1 has a flexible distal end portion so that the thermal element contacts the treatment target site. Therefore, when the thermal element disposed at the distal end portion of the catheter is disposed at the treatment target site, the force for holding the thermal element at the treatment target site is not sufficient. For this reason, there is a possibility that the thermal element may be displaced due to an unexpected impact on the catheter. In such a case, in the ablation catheter described in Patent Document 1, it is necessary to rearrange the thermal element while avoiding the site that has already been treated. However, the catheter of Patent Document 1 is flexible at the distal end portion of the catheter, so that it is not easy to rearrange while avoiding a site that has already been treated, and there is a possibility that the treatment time will be prolonged. Further, when the catheter is rearranged, there is a possibility that the treatment site due to the thermal element is concentrated at a specific location in the living body lumen and a stenosis portion is formed in the living body lumen.

  The present invention has been made to solve the problems associated with the above-described prior art, and an object thereof is to provide an ablation catheter that can easily shorten the treatment time. It is another object of the present invention to provide a catheter that can reliably make the position where the thermal element contacts when the treatment with the ablation catheter is made different between the axial direction and the circumferential direction.

  In order to achieve the above object, the present invention provides a shaft portion having a first tip portion and a second tip portion, which is inserted into a lumen in a living body, and connects the first tip portion and the second tip portion. A coupling mechanism that performs the first thermal element and the second thermal element that thermally affect the living tissue, a first bending mechanism that bends the first distal end portion of the shaft portion, and a second distal end portion of the shaft portion. And an ablation catheter having a second bending mechanism for bending. The first distal end portion includes a first region extending toward the distal end side relative to the coupling mechanism, a second region extending toward the proximal end side relative to the coupling mechanism, and the second distal end portion includes the coupling mechanism. A third region extending further to the distal end side, and a fourth region extending to the proximal end side than the coupling mechanism. The connecting mechanism is configured such that at least a part of the first region and at least a part of the third region contact the wall tissue of the lumen when the first tip and the second tip are curved. Further, the first region and the third region are separated from each other, and at least a part of the second region and at least a part of the fourth region are in contact with the wall tissue of the lumen. The second region and the fourth region are configured to be separated from each other. The first thermal element is disposed in the first region, and the second thermal element is disposed in the second region.

  According to the present invention, when the first thermal element and the second thermal element are brought into contact with the wall tissue of the lumen that is the treatment target site related to the diseased part by bending the first distal part and the second distal part, The first region of the first tip and the third region of the second tip are separated from each other, and the second region of the first tip and the fourth region of the second tip are separated from each other. Therefore, in the ablation catheter of the present invention, at least a part of the first region, at least a part of the second region, at least a part of the third region, and at least a part of the fourth region are the walls of the lumen in the living body. Contact each tissue. That is, the first tip portion and the second tip portion connected by the connecting mechanism come into contact with the wall tissue of the lumen in the living body at least at four points. Thereby, the force for maintaining the positions of the first thermal element and the second thermal element is increased, and the occurrence of unexpected displacement of the first thermal element and the second thermal element is suppressed. Therefore, it is not necessary to rearrange the first thermal element and the second thermal element while avoiding a site where treatment has already been performed, and the treatment time is easily shortened. That is, it is possible to provide an ablation catheter that can easily shorten the treatment time. In the ablation catheter of the present invention, since the first thermal element and the second thermal element arranged at the first distal end are present at positions separated by the coupling mechanism, the ablation treatment sites are concentrated, and the constriction portion It is possible to suppress the risk of occurrences of

  A third thermal element and a fourth thermal element that thermally affect biological tissue, wherein the third thermal element is disposed in the third region, and the fourth thermal element is disposed in the fourth region. It is preferable that they are arranged. In this case, it is possible to further shorten the treatment time. Further, in the catheter of the present invention, since the thermal elements are arranged at different locations in the axial direction or circumferential direction of the wall tissue of the lumen by the coupling mechanism, there is a risk that the ablation treatment locations are dense and a stenosis or the like occurs. Can also be suppressed.

  The coupling mechanism includes a first intermediate region located between the first region and the second region of the first tip portion, and a space between the third region and the fourth region of the second tip portion. It is preferable to have the axial part which connects the 2nd intermediate | middle area | region located in slidably. In such a case, when the first tip portion and the second tip portion are curved, the first intermediate region of the first tip portion and the second intermediate region of the second tip portion pivot about the shaft portion, As a result, the first region of the first tip and the third region of the second tip are separated from each other, and the second region of the first tip and the fourth region of the second tip are separated from each other. It will be. That is, it is possible to simplify the configuration of the coupling mechanism.

  The first tip is bent in a first direction by the first bending mechanism, and the second tip is bent in a second direction by the second bending mechanism, The first direction and the second direction are preferably opposite directions. In such a case, the first region of the first tip and the third region of the second tip are separated from each other, and the second region of the first tip and the fourth region of the second tip are The first tip portion and the second tip portion can be reliably bent so as to be separated from each other. Here, “the first direction and the second direction are opposite directions” means that the first cross-section in the axial direction of the shaft portion is the first relative to the plane passing through the shaft base end portion and the coupling mechanism. The direction in which the distal end of the distal end is curved and the direction in which the distal end of the second distal end is curved with respect to a plane passing through the shaft base end and the coupling mechanism are opposite directions.

  When the first to fourth thermal elements are made of monopolar electrodes, the configuration can be simplified.

  It is preferable that the first thermal element is disposed at a distal end of the first distal end portion, and the third thermal element is disposed at a distal end of the second distal end portion. In this case, it is easy to contact the first thermal element and the third thermal element with the wall tissue of the lumen.

  The first bending mechanism has a first pulling wire for bending the first tip portion, and the second bending mechanism has a second pulling wire for bending the second tip portion. Preferably it is. In this case, the configuration can be simplified.

It is the schematic for demonstrating the ablation system which has an ablation catheter which concerns on embodiment of this invention. It is a top view for demonstrating the ablation catheter shown by FIG. It is a side view for demonstrating the ablation catheter shown by FIG. It is sectional drawing for demonstrating the use of an ablation catheter. It is sectional drawing for demonstrating the positional relationship of the 1st-4th electrode arrange | positioned at an ablation catheter. It is sectional drawing for demonstrating the 1st front-end | tip part and 2nd front-end | tip part of the shaft part of an ablation catheter. FIG. 7 is a cross-sectional view taken along line VII (A) -VII (A) in FIG. 6 and line VII (B) -VII (B) in FIGS. 2 and 6. It is a top view for demonstrating the shaft main-body part of a 1st front-end | tip part and a 2nd front-end | tip part. It is sectional drawing for demonstrating the hand operation part of an ablation catheter. It is sectional drawing for demonstrating an example of the usage method of an ablation system. It is a side view for demonstrating the modifications 1-3 which concern on embodiment of this invention. It is sectional drawing for demonstrating the modification 4 which concerns on embodiment of this invention. It is a top view for demonstrating the modification 5 which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

  FIG. 1 is a schematic view for explaining an ablation system having an ablation catheter according to an embodiment of the present invention, and FIGS. 2 and 3 are plan views and side views for explaining the ablation catheter shown in FIG. FIG. 4 is a cross-sectional view for explaining the use of the ablation catheter, and FIG. 5 is a cross-sectional view for explaining the positional relationship between the first to fourth electrodes arranged in the ablation catheter.

  The ablation system 100 according to the embodiment of the present invention is applied, for example, for treatment aimed at lowering blood pressure in a treatment-resistant hypertensive patient, and as shown in FIG. 1, an ablation catheter 110, an energy supply device 190, and A counter electrode 198 is provided.

  The ablation catheter 110 includes a shaft portion 112 that is inserted into a lumen in a living body, and a hand operation portion 160 that is operated by a surgeon at hand. The lumen in the living body is an aorta 300 and a renal artery 310 as shown in FIG. Hereinafter, the side to be inserted into the lumen is referred to as “tip” or “tip side”, and the proximal side for operation is referred to as “base end” or “base end side”.

  The shaft portion 112 has a shaft base end portion 113, and a first tip portion 120 and a second tip portion 140 that are divided into two forks at the tip of the shaft base end portion 113. Further, the shaft portion 112 includes a connecting mechanism 118 that connects the first tip portion 120 and the second tip portion 140. The first tip portion 120 includes a first electrode tip 122, a second electrode tip 124, a first temperature measuring portion 126, a second temperature measuring portion 127, and a first pulling wire 128. The second tip portion 140 includes a third electrode tip 142, a fourth electrode tip 144, a third temperature measuring portion 146, a fourth temperature measuring portion 147, and a second pulling wire 148. The first tip portion 120 and the second tip portion 140 have substantially the same configuration, and the third electrode tip 142 and the fourth electrode tip 144 correspond to the first electrode tip 122 and the second electrode tip 124, respectively. ing.

  As shown in FIGS. 2 and 3, the first distal end portion 120 of the shaft portion 112 has a first region 121 </ b> A extending to the distal end side with respect to the coupling mechanism 118 and the proximal end side with respect to the coupling mechanism 118. The second region 121C, and the first intermediate region 121B connecting the first region 121A and the second region 121C. Further, the second distal end portion 140 of the shaft portion 112 includes a third region 141A extending to the distal end side from the coupling mechanism 118, a fourth region 141C extending to the proximal end side from the coupling mechanism 118, and a third region. A second intermediate region 141B that connects the region 141A and the fourth region 141C. When the first tip portion 120 and the second tip portion 140 are bent, the first region 121A and the third region 141A are separated from each other, and the second region 121C and the fourth region 141C are separated from each other. It is configured as follows. Thereby, when the first tip portion 120 and the second tip portion 140 are bent, the tip of the first region 121A and the tip of the third region 141A are bent in a direction away from the connection mechanism 118 in the circumferential direction. Accordingly, the distal end portion of the first region 121A and the distal end portion of the third region 141A are in contact with the wall tissue of the lumen. Further, when the first tip portion 120 and the second tip portion 140 are bent, the space formed by the second region 121C, the fourth region 141C, the coupling mechanism 118, and the shaft base end portion 113 is circular or elliptical. And expand to contact the wall tissue of the lumen. Therefore, the middle part of the second region 121C and the middle part of the fourth region 141C are in contact with the wall tissue of the lumen.

The first to fourth electrode tips 122, 124, 142, and 144 impart heat to the wall tissues T _{1 to} T ₄ (see FIG. 4) of the lumen, which are treatment target sites related to the diseased part, and are thermally denatured. This is a thermal element that is made up of monopolar electrodes. Thermal degeneration of the tissue is, for example, cauterization or necrosis of the fibers of the renal sympathetic nerve 320 that runs around the renal artery 310.

  The first to fourth temperature measuring units 126, 127, 146, and 147 are thermocouples, and are used to measure the heating temperature of the ablation. The tip of the first temperature measuring unit 126 is fixed to the first electrode tip 122 of the first tip 120 and is configured to measure the temperature of the first electrode tip 122. The tip of the second temperature measuring unit 127 is fixed to the second electrode tip 124 of the first tip 120, and is configured to measure the temperature of the second electrode tip 124. The tip of the third temperature measuring unit 146 is fixed to the third electrode tip 142 of the second tip 140, and is configured to measure the temperature of the third electrode tip 142. The tip of the fourth temperature measuring unit 147 is fixed to the fourth electrode tip 144 of the second tip portion 140, and is configured to measure the temperature of the fourth electrode tip 144.

The first pulling wire 128 bends the first distal end portion 120, thereby bringing the distal end portion of the first region 121A and the intermediate portion of the second region 121C into contact with the wall tissues T ₁ and T ₂ of the lumen. A bending mechanism is configured. Note that the intermediate portion of the second region 121C that comes into contact with the wall tissue of the lumen is a portion that becomes the starting point when the first tip portion 120 is bent. The second puller wire 148 bends the second distal end portion 140, thereby bringing the distal end portion of the third region 141A and the intermediate portion of the fourth region 141C into contact with the lumen wall tissues T ₃ and T ₄ . A bending mechanism is configured. Note that the intermediate portion of the fourth region 141C that contacts the wall tissue of the lumen is a portion that becomes the starting point when the second tip portion 140 is bent.

  The connection mechanism 118 separates the first region 121A and the third region 141A from each other and the second region 121C and the fourth region 141C when the first tip part 120 and the second tip part 140 are curved. It is comprised so that it may mutually space apart (refer FIG. 3). Specifically, when the first tip portion 120 and the second tip portion 140 are curved, the tip of the first tip portion 120 (tip of the first region 121A) and the tip of the second tip portion 140 (third region 141A). Of the first tip portion 120 (the middle portion of the second region 121C) and the second tip portion 140 of the portion of the starting point (fourth region). 141C (intermediate portion of 141C) is allowed to be separated from each other.

  The hand operation unit 160 is configured to pull the first pulling wire 128 and the second pulling wire 148 to bend the tip portion of the shaft portion 112.

As shown in FIG. 5, the first electrode tip 122 has a first tip so that the first tip 120 is brought into contact with the wall tissue T ₁ when the tip of the first tip 120 contacts the wall tissue T _1. The unit 120 is arranged. The second electrode chip 124, when the portion which becomes the starting point of the curvature of the first tip portion 120 contacts the wall tissue T _2, so as to contact is entrained in the wall tissue T _2, is disposed on the first distal end portion 120 The The third electrode tip 142, the tip of the second tip portion 140 when in contact with the wall tissue T _3, are entrained so as to contact the wall tissue T _3, is disposed in the second distal end portion 140. The fourth electrode tip 144, when the portion which becomes the starting point of the curvature of the second tip portion 140 contacts the wall tissue T _4, so as to contact is entrained in the wall tissue T _4, is disposed on the second distal end portion 140 The

  The energy supply device 190 is a high-frequency generator that is connected or built in a computing means such as a computer, and has a first cable 194 and a second cable 196.

  The first cable 194 is connected to the ablation catheter 110 via the connector 192. The connector 192 is connected to the first to fourth electrode chips 122, 124, 142, 144 and the first to fourth temperature measuring units 126, 127, 146, 147.

  Accordingly, the energy supply device 190 supplies a high-frequency current to the first to fourth electrode chips 122, 124, 142, and 144 via the first cable 194 and the connector 192, and the first to fourth temperature measuring units. By detecting and measuring voltages generated at 126, 127, 146, and 147, the temperatures of the first electrode chip 122 and the third electrode chip 142 can be measured. That is, the energy supply device 190 can control the heating temperature, the heating time, and the like while monitoring the heating temperature of the ablation.

  The second cable 196 is connected to the counter electrode plate 198. The counter electrode plate 198 forms a counter electrode with the first to fourth electrode chips 122, 124, 142, 144, and is attached to the body surface of the living body. As a result, a circuit is formed between the energy supply device 190, the first to fourth electrode chips 122, 124, 142, 144, the living body, and the counter electrode plate 198.

  The high-frequency current supplied from the energy supply device 190 flows into the living tissue via the first to fourth electrode chips 122, 124, 142, and 144, and returns to the counter electrode plate 198. Heat is generated. The wall tissue of the lumen that is the contact surface between the first to fourth electrode chips 122, 124, 142, and 144 and the living tissue (the treatment target site that includes the renal sympathetic nerve 320 that runs around the renal artery 310) has an electric current. Concentration causes a local temperature rise due to Joule heat. This promotes thermal degeneration of the tissue, for example, cauterization, necrosis or detachment of the fibers of the renal sympathetic nerve 320.

Ablation catheter 110, as described above, by bending the first end 120 and a second distal portion 140, contacting the first to fourth electrode tip 122,124,142,144 to the wall tissue _T 1 through T ₄ When doing so, the tip of the first tip portion 120 and the tip of the second tip portion 140 are separated from each other, and the portion of the first tip portion 120 that is the starting point of bending and the starting point of the second tip portion 140 are bent. The parts are spaced apart from each other and contact the wall tissues T _{1 to} T ₄ , respectively. In other words, the first tip portion 120 and the second tip portion 140 connected by the connecting mechanism 118 have at least four points (the tip of the first tip portion 120, the portion serving as the starting point of bending of the first tip portion 120, the second tip end). The tip of the portion 140 and the portion of the second tip 140 that is the starting point of bending) are supported. As a result, the force for holding the positions of the first to fourth electrode tips 122, 124, 142, and 144 increases, and the first to fourth electrode tips 122, 124, 142, and 144 are displaced unexpectedly. Since the generation is suppressed, it is not necessary to rearrange the first to fourth electrode tips 122, 124, 142, and 144 while avoiding the site that has already been treated, and the treatment time is easily shortened. The

  Further, the first to fourth electrode chips 122, 124, 142, 144 are composed of monopolar electrodes, and the configuration is simplified.

  In addition, since the four electrode tips 122, 124, 132, and 136 are provided as thermal elements for applying energy to the wall tissue of the lumen to thermally denature, it is possible to shorten the treatment time. .

  The ablation catheter 110 can also have an impedance sensor that checks the contact state between the electrode tip and the living tissue. If necessary, a direct current can be applied as ablation energy instead of the high-frequency current.

  The first to fourth temperature measuring units 126, 127, 146, and 147 are not limited to a configuration constituted by thermocouples made of two different types of metal wires, and for example, a thermistor can also be applied.

  Next, the shaft portion 112 and the hand operation portion 160 of the ablation catheter 110 will be described in detail.

  6 (A) and 6 (B) are cross-sectional views for explaining the first tip and second tip of the shaft portion of the ablation catheter of FIG. 2, and FIG. 7 (A) is FIG. 6 (A). ) In FIG. 7B is a cross-sectional view taken along line VII (A) -VII (A), FIG. 7B is a cross-sectional view taken along line VII (B) -VII (B) in FIG. 2 and FIG. ) And FIG. 8B are plan views for explaining the shaft main body portion of the first front end portion and the shaft main body portion of the second front end portion.

  The shaft portion 112 of the ablation catheter 110 has the first tip portion 120 and the second tip portion 140 connected by the connecting mechanism 118 as described above.

  As shown in FIGS. 6A and 7A, the first tip portion 120 has a first shaft main body portion 130 and a covering portion 116 that covers the first shaft main body portion 130, and The first electrode chip 122 and the second electrode chip 124 are arranged. As shown in FIG. 6B, the second tip portion 140 includes a second shaft main body portion 150 and a covering portion 116 that covers the second shaft main body portion 150, and the third electrode tip 142. And the 4th electrode chip | tip 144 is arrange | positioned. Note that, as shown in FIG. 7B, the first tip portion 120 and the first tip portion 120 are integrated on the proximal end side of the shaft portion 112.

  The first shaft main body 130 and the second shaft main body 150 are long tubular bodies, and include lead wires 123, 125 and 143, 145, first to fourth temperature measuring units 126, 127, 146, 147, A first puller wire 128 and a second puller wire 148 extend through the interior. The lead wires 123, 125, 143, 145 and the first to fourth temperature measuring units 126, 127, 146, 147 are connected to the energy supply device 190 as described above. Note that the lead wires 123, 125, 143, 145 and the first to fourth temperature measuring units 126, 127, 146, 147 have insulating coating layers, but are omitted in the drawing.

  As shown in FIGS. 8A and 8B, the first shaft main body 130 and the second shaft main body 150 are composed of a first flexible portion 132 and 152, a second flexible portion 134 and 154, and a high rigidity. Parts 136 and 156. The outer diameter and thickness of the first shaft main body 130 and the second shaft main body 150 are, for example, 0.5 to 3.0 mm and 100 to 300 μm.

  The first flexible parts 132 and 152 and the second flexible parts 134 and 154 are formed with spiral slits 138 and 158. The second flexible parts 134 and 154 are located between the first flexible parts 132 and 152 and the high rigidity parts 136 and 156. The slits 138 and 158 are formed continuously (integrally) by, for example, laser processing.

Pitch _{P 1} of the slits 138,158 in the first flexible portion 132, 152 is set smaller than the pitch _{P 2} of the slits 138,158 in the second flexible portion 134 and 154. For example, the pitch P ₁ is 0.2 to ₁ . Is 0mm, the pitch _{P 2} is a 1.0~2.0mm. The pitches P ₁ and P ₂ are intervals between the adjacent slits 138 and 158.

  Since the first flexible parts 132 and 152 and the second flexible parts 134 and 154 are formed with slits 138 and 158, the bending rigidity is reduced and the first flexible parts 134 and 154 have a flexible structure that is easy to bend. The first flexible portions 132 and 152 have a lower bending rigidity than the second flexible portions 134 and 154 because the pitch P of the slits 138 and 158 is narrower than the second flexible portions 134 and 154.

  The high-rigidity parts 136 and 156 are located on the base end side, are not formed with the spiral slits 138 and 158, and have higher bending rigidity than the first flexible parts 132 and 152 and the second flexible parts 134 and 154. ing.

  Since the first flexible portions 132 and 152 and the second flexible portions 134 and 154 having low bending rigidity and flexible are located at the distal end sides of the first shaft main body portion 130 and the second shaft main body portion 150, the lumen in the living body. The first tip portion 120 and the second tip portion 140 of the shaft portion 112 can easily pass through the curved portion, and high reachability and operability can be obtained. Moreover, since the high rigidity parts 136 and 156 with high bending rigidity are located on the proximal end sides of the first shaft main body part 130 and the second shaft main body part 150, sufficient pushability of the shaft part 112 is ensured.

  The length of the first flexible portion 132 and the length of the second flexible portion 134 are the distance from the first electrode tip 122 to the second electrode tip 124, the length after branching at the first tip portion 120, and the tube to be inserted. It is appropriately set in consideration of the configuration of the cavity. The length of the first flexible portion 152 and the length of the second flexible portion 154 are the distance from the third electrode tip 142 to the fourth electrode tip 144, the length after branching at the second tip portion 140, and the tube to be inserted. It is appropriately set in consideration of the configuration of the cavity.

  The 1st shaft main-body part 130 and the 2nd shaft main-body part 150 are not limited to the form which has two flexible parts from which the pitch of a slit differs. The pitch of the slits can be set so as to change gradually. The slit is not limited to a spiral shape.

  The first electrode tip 122 and the third electrode tip 142 have a hemispherical shape, and constitute the tip of the first shaft body 130 and the tip of the second shaft body 150. Therefore, it is easy to bring the first electrode tip 122 and the third electrode tip 142 into contact with the wall tissue of the lumen, and damage to the wall tissue that comes into contact is suppressed. The first electrode tip 122 and the third electrode tip 142 are not limited to a hemispherical shape. Further, the first electrode tip 122 and the third electrode tip 142 are not limited to the form constituting the tip of the first shaft main body 130 and the tip of the second shaft main body 150. For example, It is also possible to configure only a part of the tip and only a part of the tip of the second shaft main body 150.

  The first electrode tip 122 is fixed at the tip of the lead wire 123 and the tip of the first temperature measuring portion 126, and the third electrode tip 142 is fixed at the tip of the lead wire 143 and the tip of the third temperature measuring portion 146. Yes. The lead wire 123 and the lead wire 143 are used to supply a high-frequency current from the energy supply device 190 to the first electrode chip 122 and the third electrode chip 142. As described above, the first temperature measuring unit 126 and the third temperature measuring unit 146 measure the temperature of the first electrode chip 122 and the temperature of the third electrode chip 142, and are used for monitoring and controlling the heating of the ablation. Is done.

  The second electrode tip 124 and the fourth electrode tip 144 have an arcuate cross section (see FIG. 5). The second electrode tip 124 is disposed at a portion of the first tip portion 120 that is the starting point of bending, and the lead wire 125 and the tip of the second temperature measuring portion 127 are fixed. The fourth electrode tip 144 is disposed at a portion that is the starting point of bending of the second tip portion 140, and the lead wire 145 and the tip of the fourth temperature measuring portion 147 are fixed. The lead wire 125 and the lead wire 145 are used to supply a high-frequency current from the energy supply device 190 to the second electrode chip 124 and the fourth electrode chip 144. As described above, the second temperature measuring unit 127 and the fourth temperature measuring unit 147 are used to measure the temperature of the second electrode tip 124 and the fourth electrode tip 144 and to monitor and control the heating of the ablation. . In addition, the 2nd electrode chip | tip 124 and the 4th electrode chip | tip 144 are not limited to the form which has an arc-shaped cross section, For example, it is also possible to have a rectangular-shaped cross section.

  The first pulling wire 128 constitutes a first bending mechanism of the first tip portion 120. The first pulling wire 128 is fixed to the inner wall of the first shaft main body 130 between the distal end side between the first electrode tip 122 and the portion where the coupling mechanism 118 is disposed, and the proximal end side to the wire fixing portion 167. It is fixed. Therefore, by pulling the first pulling wire 128 by the hand operation unit 160, the distal end side of the first shaft main body 130 is pulled, and the first flexible portion 132 and the first flexible portion 132 of the first shaft main body 130 extending in a substantially linear shape. The part including the two flexible parts 134 can be bent. That is, by pulling the first pulling wire 128 by the hand operation unit 160, the tip of the first tip portion 120 of the shaft portion 112 can be bent. Further, by loosening the traction by the first traction wire 128, the first tip portion 120 of the shaft portion 112 is restored to the original by the elastic force of the first flexible portion 132 and the second flexible portion 134 of the first shaft main body portion 130. It can be returned to a substantially linear shape.

  The second puller wire 148 constitutes a second bending mechanism of the second tip portion 140. The second puller wire 148 has a distal end side fixed between the third electrode tip 142 and the portion where the coupling mechanism 118 is disposed, and a proximal end side fixed to the wire fixing portion 167. Therefore, by pulling the second pulling wire 148 by the hand operation unit 160, the distal end side of the second shaft main body 150 is pulled, and the first flexible portion 152 and the first flexible portion 152 of the second shaft main body 150 extending in a substantially linear shape. 2 The part including the flexible part 154 can be bent. That is, by pulling the second pulling wire 148 by the hand operation unit 160, the tip of the second tip portion 140 of the shaft portion 112 can be bent. In addition, by loosening the pulling by the second pulling wire 148, the second tip portion 140 of the shaft portion 112 is restored to the original by the elastic force of the first flexible portion 152 and the second flexible portion 154 of the second shaft main body portion 150. It can be returned to a substantially linear shape.

  As described above, the first pulling wire 128 and the second pulling wire 148 are pulled by the hand operation unit 160 to bend the first tip portion 120 and the second tip portion 140. That is, when a pulling wire is applied to the first bending mechanism and the second bending mechanism, the configuration can be simplified. Further, the first pulling wire 128 and the second pulling wire 148 can be integrated on the proximal end side.

  The coupling mechanism 118 is capable of pivoting between the first intermediate region 121B (see FIG. 6A) of the first tip portion 120 and the second intermediate region 141B (see FIG. 6B) of the second tip portion 140. Consists of connecting shafts. The first intermediate region 121B is located between the first electrode tip 122 (the tip of the first tip portion 120) and the second electrode tip 124 (the portion that is the starting point of the bending of the first tip portion 120). The second intermediate region 141B is located between the third electrode tip 142 (the tip of the second tip portion 140) and the fourth electrode tip 144 (the portion that is the starting point of the curvature of the second tip portion 140).

  Therefore, when the first tip portion 120 and the second tip portion 140 are curved, the first intermediate region 121B and the second intermediate region 141B pivot in the opposite direction around the shaft portion (the coupling mechanism 118). As a result, the first electrode tip 122 (tip of the first tip portion 120) and the third electrode tip 142 (tip of the second tip portion 140) are separated from each other, and the second electrode tip 124 (first tip portion). 120) and a fourth electrode tip 144 (a part of the second tip portion 140 serving as a starting point of bending) are separated from each other. That is, the configuration of the coupling mechanism is simplified.

The first tip portion 120 is bent in the first direction by the first bending mechanism, and the second tip portion 140 is configured to be bent in the second direction by the second bending mechanism. The direction and the second direction are preferably opposite directions. Specifically, the first end 120 and second tip 140 has a curved likely direction, the direction _{D 1} to the curvature of the first tip portion 120, the direction _{D 2} of curvature of the second distal portion 140 Are preferably opposite directions (see FIG. 3). In such a case, the tip of the first tip portion 120 and the tip of the second tip portion 140 are separated from each other, and the portion of the first tip portion 120 that is the starting point of bending and the starting point of the second tip portion 140 are bent. Are separated from each other. Therefore, the wall tissue in which the first electrode tip 122 and the third electrode tip 142 are separated in the living body lumen and the second electrode chip 124 and the fourth electrode tip 144 are separated in the living body lumen. To touch. Thereby, the ablation treatment location can be concentrated, and the risk of a stenosis etc. can be suppressed.

  The direction in which bending is easy can be controlled, for example, by providing portions with different stiffnesses in the circumferential direction of the first shaft main body 130 and the second shaft main body 150. Sites having different stiffnesses can be formed by locally changing the thickness or the configuration of the slits 138 and 158 or arranging a reinforcing material.

  The first shaft main body 130 and the second shaft main body 150 are made of a metal material having relatively high rigidity, for example, Ni-Ti, brass, SUS, or aluminum. It is also possible to apply a polymer material having relatively high rigidity such as polyimide, vinyl chloride, or polycarbonate.

  The covering 116 is made of a polymer material having insulating properties, such as polyolefin, a cross-linked polyolefin, polyvinyl chloride, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polyurethane elastomer, fluororesin, or polyimide. Examples of the polyolefin include polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, and ionomer. It is also possible to apply a mixture of the above polymer materials.

  Next, the hand operation unit 160 of the ablation catheter 110 will be described.

  9A and 9B are cross-sectional views for explaining the distal end side and the proximal end side of the proximal operation portion of the ablation catheter.

  The hand operation unit 160 includes an operation main body unit 162 and a slide unit 180 as shown in FIGS. 9 (A) and 9 (B). The operation main body 162 is a part held by the operator. The slide portion 180 is slidable and close to the operation main body portion 162 in a slidable manner, and is operated so as to be close to the operation main body portion 162 by an operator. And the tip of the shaft portion 112 is bent. Note that the base portion 114 of the shaft portion 112 is introduced into the slide portion 180.

  The operation main body portion 162 has a substantially cylindrical shape, and includes an operation main body inner tube portion 164, an outer tube portion 174, and a connector 176.

  The operation main body inner cylinder portion 164 is in contact with the slide portion 180 so as to be slidable, and includes a screw thread 165, a wire fixing portion 167, and a guide pin 168. The thread 165 is formed on the outer peripheral surface on the distal end side of the operation main body inner cylinder portion 164. The wire fixing portion 167 is formed inside the operation main body inner cylinder portion 164, and the proximal ends of the first pulling wire 128 and the second pulling wire 148 are fixed. The guide pin 168 is fixed so as to protrude from the inner peripheral surface that slides with the slide portion 180.

  The outer cylinder part 174 has a thread groove 175 and is arranged so as to cover the outer periphery of the operation main body inner cylinder part 164. The thread groove 175 is formed on the inner peripheral surface on the distal end side, and is configured to be freely engageable with the thread 165 of the operation main body inner cylinder portion 164. Therefore, by engaging the thread groove 175 with the thread 165 of the operation main body inner cylinder part 164, the outer cylinder part 174 can be fixed to the operation main body inner cylinder part 164.

  The connector 176 has terminals 177A to 177F, 178A to 177F and a socket 179, and is arranged at the proximal end portion inside the operation main body inner cylinder portion 164. The terminals 177A to 177F are connected to the lead wire 123 (first electrode chip 122), the lead wire 125 (second electrode chip 124), the first temperature measuring unit 126, and the second temperature measuring unit 127. Terminals 178A to 178F are connected to lead wire 143 (third electrode chip 142), lead wire 145 (fourth electrode chip 144), third temperature measuring unit 146, and fourth temperature measuring unit 147. The socket 179 is configured such that the connector 192 of the first cable 194 extending from the energy supply device 190 is detachable.

  The slide part 180 has a slide inner cylinder part 182, a disk-like operation part 186 and a kink resistant tube 188, and the base part 114 of the shaft part 112 is introduced.

  The slide inner cylinder part 182 has a guide groove 184 and is slidably accommodated inside the front end side of the operation main body inner cylinder part 164 of the operation main body part 162. The guide groove 184 is formed on the outer peripheral surface of the operation main body portion 162 that slides with the operation main body inner cylinder portion 164, extending in the axial direction S, and extending from the operation main body inner cylinder portion 164 of the operation main body portion 162. 168 is movably accommodated. Therefore, the slide inner cylindrical portion 182 (slide portion 180) is allowed to move in the axial direction S with respect to the operation main body portion 162 and is restricted from moving in the rotational direction with respect to the operation main body portion 162.

  The disk-shaped operation part 186 has a through hole 187, is located on the distal end side of the slide inner cylinder part 182, and is used to pull the first pulling wire 128 and the second pulling wire 148. The outer diameter of the disk-shaped operation part 186 is set larger than the outer diameter of the operation main body part 162, which makes it easy for the operator to operate. The through hole 187 communicates with the inside of the slide inner cylinder portion 182.

  The kink resistant tube 188 has a through-hole 189 and is disposed on the distal end side of the disk-like operation unit 186. The through-hole 189 is aligned with the through-hole 187 of the disk-like operation portion 186 and is used to introduce the base portion 114 of the shaft portion 112 into the slide inner cylinder portion 182 in cooperation with the through-hole 187. The kink resistant tube 188 has a function of preventing kinking (bending) of the shaft portion 112 in the vicinity of the distal end of the disk-like operation portion 186 (slide portion 180).

  For the operation main body portion 162 and the slide portion 180, for example, a polymer material such as ABS resin, polycarbonate, polyamide, polysulfone, polyarylate, methacrylate-butylene-styrene copolymer is applied. It is also possible to apply a mixture of the above polymer materials.

  Next, an example of how to use the ablation system will be described.

  FIG. 10A is a cross-sectional view for explaining the insertion of the guiding catheter, and FIG. 10B is a cross-sectional view for explaining the insertion of the shaft portion of the ablation catheter following FIG. 10A. is there.

  First, the connector 192 of the first cable 194 of the energy supply device 190 is connected to the socket 179 of the operation main body 162 of the hand operation unit 160, and the counter electrode plate 198 connected to the second cable 196 of the energy supply device 190 is Affixed to the patient's body surface.

  A sheath is attached percutaneously to the radial artery in the right or left hand. Then, the guide wire 200 is inserted into the radial artery via the sheath, and is introduced from the radial artery through the brachial artery and the axillary artery to the vicinity of the renal artery 310 of the aorta 300.

  A guiding catheter 210 is inserted along the guide wire 200, and the distal end portion 212 of the guiding catheter 210 is guided to the entrance of the renal artery 310 as shown in FIG. Thereafter, the guide wire 200 is removed. The guide wire 200 can be introduced from a blood vessel other than the radial artery, for example, the brachial artery, the axillary artery or the femoral artery.

  The shaft portion 112 of the ablation catheter 110 is inserted into the guiding catheter 210 from the proximal end side of the guiding catheter 210 and protrudes from the distal end portion 212 of the guiding catheter 210 as shown in FIG. It is inserted into the renal artery 310 toward the one kidney 330 and positioned in the vicinity of the wall tissue of the renal artery 310 adjacent to the renal sympathetic nerve 320 that is the treatment target site.

  At this time, the shaft portion 112 exhibits high pushability and torque transmission due to the presence of the high rigidity portions 136 and 156, and the presence of the first flexible portions 132 and 152 and the second flexible portions 134 and 154 allows It can easily pass through curved parts and the like, and exhibits high reachability and operability.

  The slide part 180 is moved to the distal end side with respect to the operation main body part 162, and the first pulling wire 128 and the second pulling wire 148 are pulled.

As a result, the first intermediate region 121B of the first tip portion 120 and the second intermediate region 141B of the second tip portion 140 turn in opposite directions around the shaft portion (the coupling mechanism 118), and the first electrode tip 122 is rotated. (The tip of the first tip portion 120) and the third electrode tip 142 (the tip of the second tip portion 140) are separated from each other, and the second electrode tip 124 (the starting point of bending of the first tip portion 120) ) And the fourth electrode tip 144 (parts from which the second tip portion 140 is curved) are separated from each other. Thus, first to fourth electrode tip 122,124,142,144 is in contact with the wall tissue _{T 1, T 2, T 3} , T 4 ( see FIG. 4), the energy supply device 190, first to A circuit is formed between the four-electrode chips 122, 124, 142, 144, the living body, and the counter electrode plate 198.

  At this time, the first tip portion 120 and the second tip portion 140 connected by the connecting mechanism 118 have at least four points (the tip of the first tip portion 120, the portion serving as the starting point of bending of the first tip portion 120, the second The distal end of the distal end portion 140 and the portion of the second distal end portion 140 that is the starting point of bending) are supported. That is, the force for holding the positions of the first to fourth electrode tips 122, 124, 142, and 144 increases, and an unexpected displacement of the first to fourth electrode tips 122, 124, 142, and 144 occurs. Therefore, it is not necessary to rearrange the first to fourth electrode tips 122, 124, 142, and 144 while avoiding the site that has already been treated, and the treatment time can be easily shortened. .

When a high-frequency current is supplied from the energy supply device 190, it flows into the living tissue via the first to fourth electrode tips 122, 124, 142, and 144, and returns to the counter electrode plate 198. Joule heat is generated. The lumen wall tissues T ₁ , T ₂ , T ₃ , and T ₄ , which are contact surfaces between the first to fourth electrode tips 122, 124, 142, and 144 and the living tissue, are concentrated due to Joule heat. A local temperature rise is caused.

  For example, the high frequency is 350 to 750 kHz, the high frequency electric energy is 0.1 to 8.0 W, the heating temperature is 50 to 70 ° C., and the heating time is 30 to 60 seconds.

Thus, (fibers ablation and necrosis of the renal sympathetic 320) heat denaturation of the treatment target site adjacent to the wall tissue T ₁ through T ₄ lumens (renal sympathetic nerve 320 that runs around the renal artery 310) is prompted .

When the thermal denaturation of the treatment target site is completed, the supply of high-frequency current from the energy supply device 190 is stopped. Then, the traction by the first traction wire 128 and the second traction wire 148 is loosened by moving the slide portion 180 toward the proximal end side with respect to the operation main body portion 162. Thus, the bending of the tip of the first tip portion 120 and the second distal portion 140 is eliminated becomes substantially straight, the first to fourth electrode tip 122,124,142,144 are wall tissue _T 1, _{T 2} , T ₃ and T ₄ .

  Thereafter, by operating the hand operation unit 160, the distal ends of the first tip portion 120 and the second tip portion 140 are appropriately moved and rotated, and the renal artery adjacent to the renal sympathetic nerve 320 that is the next treatment target site. It is positioned near the wall tissue of 310. For example, the moving distance of the tips of the first tip portion 120 and the second tip portion 140 is 0.3 to 1.0 mm, and the rotation angle is 90 to 270 degrees.

  Then, bending of the tips of the first tip portion 120 and the second tip portion 140 (contact with the wall tissue of the first to fourth electrode tips 122, 124, 142, 144 and support by four points), from the energy supply device 190 Start of supply of high-frequency current, thermal denaturation of the treatment target site, stop of supply of high-frequency current, elimination of bending of the tips of the first tip portion 120 and the second tip portion 140 (first to fourth electrode tips 122, 124, 142, 144 separation from the wall tissue) is performed as well.

  Then, the above treatment is repeated as appropriate so that the heat-denatured portion draws a spiral on the inner wall surface of the renal artery 310. When the treatment is completed, the same treatment is repeated as appropriate for the renal artery 310 toward the other kidney 330.

  When the treatment of the right and left renal arteries 310 is completed, the ablation catheter 110, the guiding catheter 210, and the sheath are removed, and the procedure ends. Only the left or right renal artery may be treated.

  The movement and rotation of the tips of the first tip portion 120 and the second tip portion 140 is performed by spatially changing the renal sympathetic nerve 320 located outside the renal artery outer membrane and the outer membrane in the renal artery 310. This is because heat degeneration is caused in the entire circumference, while damage in the entire circumference in the cross section in the renal artery 310 is prevented. This reduces the risk of vascular stenosis.

  Next, modifications 1 to 4 according to the embodiment of the present invention will be described in order.

  FIGS. 11A to 11C are side views for explaining Modifications 1 to 3 according to the embodiment of the present invention.

  The ablation catheter 110 is not limited to the form having the first to fourth electrode tips 122, 124, 142, 144. For example, as shown in FIGS. 11 (A) to (C), the third electrode tip 142 and / Or the fourth electrode tip 144 may be omitted as necessary.

    FIG. 12 is a cross-sectional view for explaining the modification 4 according to the embodiment of the present invention.

  The shaft portion 112 is not limited to the form having the first shaft main body portion 130 and the second shaft main body portion 150 separately (see FIG. 7B), and as shown in FIG. It is also possible to have a shaft main body base 139 in which the first shaft main body 130 and the second shaft main body 150 are integrated on the end side.

  FIG. 13: is a top view for demonstrating the modification 5 which concerns on embodiment of this invention.

  The shaft portion 112 is not limited to the form having only the first tip portion 120 and the second tip portion 140, and may have a third tip portion 159, for example, as shown in FIG. In this case, the first tip portion 120, the second tip portion 140, and the third tip portion 159 have six points (the tip of the first tip portion, the portion that is the starting point of the bending of the first tip portion, the tip of the second tip portion). The second tip portion is supported at the bending start point, the third tip tip tip, and the third tip tip bending start point).

  As described above, in the present embodiment, when the first tip portion and the second tip portion are curved to bring the first to fourth electrode tips into contact with the wall tissue, the tip of the first tip portion and the second tip The distal end of the distal end portion is spaced apart from each other, and the portion of the first distal end portion that is the starting point of bending and the portion of the second distal end portion that is the starting point of bending are separated from each other and contact the wall tissue. That is, the first tip portion and the second tip portion connected by the connecting mechanism have at least four points (the tip of the first tip portion, the portion that is the starting point of bending of the first tip portion, the tip of the second tip portion, and The second tip portion is in contact with the in-vivo wall tissue at the site of the curvature of the second tip. Thereby, the force for holding the positions of the first to fourth electrode tips is increased, and the occurrence of unexpected displacement of the first to fourth electrode tips is suppressed. For this reason, it is not necessary to rearrange the first to fourth electrodes while avoiding a site that has already been treated, and the treatment time can be easily shortened. That is, it is possible to provide an ablation catheter that can easily shorten the treatment time.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

  For example, the energy applied by the heat element is not limited to a form using resistance heating by high-frequency energization, and coherent light such as cooling, microwave, ultrasonic wave, laser, or the like can be used.

  Resistance heating by high-frequency energization is not limited to a form using a monopolar electrode and a counter electrode plate, and a bipolar electrode can also be applied.

  The treatment target region is not limited to the renal artery, and can be applied to myocardial cauterization for treating tachyarrhythmia.

  The use of ablation catheters is not limited to treatment aimed at lowering blood pressure in patients with refractory hypertension; heart failure, renal disease, chronic renal failure, sympathetic hyperactivity, diabetes, metabolic disorders, arrhythmia, acute myocardial infarction, cardiorenal It can also be applied to the treatment of syndromes and the like.

100 ablation system,
110 Ablation catheter,
112 shaft part,
113 shaft proximal end,
114 base,
116 covering part,
118 coupling mechanism,
120 first tip,
121A first region,
121B first intermediate region,
121C second region,
122 first electrode chip (thermal element),
123 lead wire,
124 second electrode chip (thermal element),
125 lead wires,
126 1st temperature measuring part (thermocouple),
127 second temperature measuring section (thermocouple),
128 first puller wire,
130 first shaft body,
132 first flexible part,
134 second flexible part,
136 High rigidity part,
138 slits,
139 Shaft body base,
140 second tip,
141A third region,
141B second intermediate region,
141C fourth region,
142 third electrode chip (thermal element),
143 lead wire,
144 Fourth electrode chip (thermal element),
145 lead wire,
146 Third temperature measuring section (thermocouple),
147 Fourth temperature measuring unit (thermocouple),
148 second puller wire,
150 second shaft body,
152 first flexible part,
154 second flexible part,
156 high rigidity part,
158 slit,
159 third tip,
160 Hand control unit,
162 operation main body,
164 operation main body inner cylinder part,
165 thread,
167 Wire fixing part,
168 guide pins,
174 outer tube,
175 thread groove,
176 connector,
177A to 177F, 178A to 178F terminals,
179 socket,
180 slide part,
182 slide inner cylinder,
184 guide groove,
186 Disc-shaped control unit,
187 through hole,
188 Anti-kink tube,
189 through hole,
190 energy supply device,
192 connector,
194 1st cable,
196 Second cable,
198 counter electrode,
200 guide wire,
210 guiding catheter,
212 tip opening,
300 aorta,
310 renal artery,
320 Renal sympathetic nerve,
330 kidney,
D ₁ and D ₂ directions,
P ₁ , P ₂ pitch,
S axis direction,
T ₁ ~T ₄ wall tissue.

Claims (7)

A shaft portion having a first tip portion and a second tip portion inserted into a lumen in a living body;
A coupling mechanism that couples the first tip portion and the second tip portion;
A first thermal element and a second thermal element that thermally affect biological tissue;
A first bending mechanism for bending the first tip portion of the shaft portion;
A second bending mechanism for bending the second tip portion of the shaft portion,
The first distal end portion includes a first region extending to the distal end side with respect to the coupling mechanism, a second region extending to the proximal end side with respect to the coupling mechanism,
The second distal end portion includes a third region extending to the distal end side with respect to the coupling mechanism, and a fourth region extending to the proximal end side with respect to the coupling mechanism,
The connecting mechanism is configured such that at least a part of the first region and at least a part of the third region contact the wall tissue of the lumen when the first tip and the second tip are curved. Further, the first region and the third region are separated from each other, and at least a part of the second region and at least a part of the fourth region are in contact with the wall tissue of the lumen. The second region and the fourth region are configured to be separated from each other,
The first thermal element is disposed in the first region;
The second thermal element is disposed in the second region;
An ablation catheter characterized by the above. A third thermal element and a fourth thermal element that thermally affect the living tissue;
The third thermal element is disposed in the third region;
The fourth thermal element is disposed in the fourth region;
The ablation catheter according to claim 1.   The coupling mechanism includes a first intermediate region located between the first region and the second region of the first tip portion, and a space between the third region and the fourth region of the second tip portion. The ablation catheter according to claim 2, further comprising a shaft portion that pivotably connects the second intermediate region located at the center. The first tip portion is bent in a first direction by the first bending mechanism,
The second tip portion is configured to bend in a second direction by the second bending mechanism,
The ablation catheter according to claim 2 or 3, wherein the first direction and the second direction are opposite directions.   The ablation catheter according to any one of claims 2 to 4, wherein the first thermal element, the second thermal element, the third thermal element, and the fourth thermal element comprise monopolar electrodes. The first thermal element is disposed at a tip of the first tip;
The ablation catheter according to any one of claims 2 to 5, wherein the third thermal element is disposed at a distal end of the second distal end portion. The first bending mechanism has a first pulling wire for bending the first tip portion,
The ablation catheter according to claim 2, wherein the second bending mechanism has a second pulling wire for bending the second tip portion.